Browsing by Author "Ullah, Muhammad Irfan"

Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Balancing Business and Technical Objectives for Supporting Software Evolution
    (Serials Publications, 2010-12) Nault, Barrie R; Ullah, Muhammad Irfan; Wei, Xuequi (David); Ruhe, Guenther
    Context: Successful software systems continuously evolve to accommodate feature requests of a diverse customer-base. At some point during this evolution, the variety of customer needs and increased system complexity suggests the consideration of a software product line (SPL). Aim: The goal of this research is to support the decision maker facing the enhancement of an evolving software system (ESS) to determine the most appropriate product line design (out of a given set of candidate SPL portfolios) to minimize the technical risk and maximize the business value. Method: The proposed method called OPTESS is aimed at finding an evolution plan for the ESS which optimizes both the given technical and business objectives. Business analysis using a value-based pricing mechanism is applied to a set of initially proposed SPL portfolios (for enhancing the ESS) such that profit is maximized. Technical analysis is applied to the same initially proposed SPL portfolios to minimize the risk of failure of ESS due to implementation of new features. Business and technical analyses improve the performance of solutions for their respective objectives by modifying the feature sets of candidate SPL portfolios. OPTESS helps the decision maker to select a plan for enhancement of ESS by performing trade-off analysis on the economic and technical objectives. Results: The method was initially evaluated by a case study for a set of 9 new candidate features to be added to an open source text editing system called jEdit. OPTESS helped the decision maker to identify 3 non-dominated solutions considered to be of highest preference for decision-making when looking at both technical and economic criteria.
  • Thumbnail Image
    ItemOpen Access
    Decision support for evolving a single software product to a software product line
    (2011) Ullah, Muhammad Irfan; Ruhe, Guenther
    Offering the right set of features to the targeted customers is a key factor in the success of market-driven software products. While planning for the next release of a single evolving software system, this thesis research addresses the decision problem: Should it be offered as a single product or a product line? Most existing approaches address this problem by focusing on either the business aspects or the technical aspects in isolation of each other. A flexible decision support framework (Contribution 1) which can be customized at different levels of sophistication is presented to address the decision problem. Three instantiations of the framework are presented as a family of decision support methods (Contribution 2). Each method tackles the decision problem with increasing level of sophistication by applying customized algorithms and techniques (Contribution 3). The first method (COPE) applies cluster analysis to identify segments of customers and proposes corresponding product portfolios. A human decision maker is involved to select a solution by informally considering architectural and economic benefits. The second method (COPE+) evaluates the impact of new features on evolving software systems' architectural structure by applying an evolutionary algorithm and a customized graph matching algorithm. This analysis reduces the solutions space and helps the decision maker to select a suitable solution. The third method (OPTESS) formally brings in the economic aspect by allowing the decision maker to perform trade-off analysis between the technical and business objectives. Three illustrative case studies are presented as proof of concepts of the proposed methods (Contribution 4). A decision support tool is provided to help the decision maker in application of the methods by automating some of the activities of these methods (Contribution 5).